WTPA42 PHFO 140929
TCDCP2
HURRICANE FLOSSIE DISCUSSION NUMBER 23
NWS CENTRAL PACIFIC HURRICANE CENTER HONOLULU HI EP092007
1100 PM HST MON AUG 13 2007
FLOSSIE IS SHOWING DEFINITE SIGNS OF WEAKENING.
OVER THE PAST 6 HOURS...AIRCRAFT RECONNAISSANCE AND SATELLITE DATA
HAVE SHOWN A CLEAR WEAKENING TREND FOR HURRICANE FLOSSIE. AIRCRAFT
OBSERVATIONS SHOWED THE CENTRAL PRESSURE HAD RISEN TO 970 MB AT
0503 UTC AND THE EYEWALL WAS OPEN TO THE SOUTHEAST. SATELLITE
IMAGERY SHOWED THE EYE DISAPPEARING BY 0500 UTC WITH THE CLOUD
PATTERN BECOMING STRETCHED OUT TOWARD THE NORTHEAST. APPARENTLY
SHEAR IS FINALLY TAKING ITS TOLL ON FLOSSIE. THE SATELLITE
ESTIMATES GAVE CI NUMBERS OF 5.5 AND 5.0. WE USED A CONSERVATIVE
100 KT FOR THE INITIAL INTENSITY. BOTH AIRCRAFT OBSERVATIONS AND A
0430 UTC QUIKSCAT PASS SHOWED A VERY ASYMMETRICAL WIND FIELD. WE
INCREASED THE WIND RADII ON THE NORTH SIDE OF FLOSSIE AND DECREASED
THEM ON THE SOUTH SIDE. THE TROPICAL STORM FORCE WINDS ARE STILL
FORECAST TO EXTEND OUT FAR ENOUGH TO THE NORTH TO AFFECT THE BIG
ISLAND AS FLOSSIE PASSES SOUTH OF THE ISLAND TOMORROW. A TROPICAL
STORM WARNING AND A HURRICANE WATCH CONTINUE FOR THE BIG ISLAND. WE
STILL EXPECT THAT NO WATCHES OR WARNINGS WILL BE REQUIRED FOR THE
ISLANDS EXCEPT THE BIG ISLAND. A NORTHWARD SHIFT IN THE TRACK COULD
CHANGE THIS EXPECTATION...BUT THE RECENT WEAKENING TREND MAKES IT
LESS LIKELY THAT FLOSSIE WILL HAVE A MAJOR IMPACT OUTSIDE OF THE
BIG ISLAND.
TRACK GUIDANCE HAS BECOME A BIT LESS TIGHTLY PACKED OVER THE PAST 6
HOURS BUT GENERALLY SHOWS A CONTINUED WEST NORTHWEST TRACK. WE HAVE
KEPT THE TRACK NEARLY THE SAME EXCEPT FOR A SLIGHT SHIFT SOUTH
AFTER 72 HOURS. THIS IS DUE TO THE EXPECTATION THAT FLOSSIE WILL
WEAKEN FAIRLY RAPIDLY AND TRACK CLOSER TO THE LOW LEVEL STEERING
FLOW.
FORECAST POSITIONS AND MAX WINDS
INITIAL 14/0900Z 16.4N 153.2W 100 KT
12HR VT 14/1800Z 17.2N 155.2W 85 KT
24HR VT 15/0600Z 18.0N 157.3W 75 KT
36HR VT 15/1800Z 19.0N 159.8W 65 KT
48HR VT 16/0600Z 19.8N 162.2W 55 KT
72HR VT 17/0600Z 21.0N 166.0W 40 KT
96HR VT 18/0600Z 22.2N 170.1W 35 KT
120HR VT 19/0600Z 23.4N 174.0W 25 KT
$$
FORECASTER DONALDSON